1. Field of the Invention
The disclosed technique belongs to the technical field of manufacturing quadrangular packing bags which are in quadrangular barrel shape having a quadrangular cross section, a bottom plane being flat and a top plane being onesidedly slant with its lapped edge portion being squeezed and sealed by means of heat seal, adhesive or the like and which are filled with block and powder merchandise such as light and bulky snack confectionery or the like and seasonings or the like or liquid and viscous merchandise such as juice and others by a predetermined weight or volume and contained in cases of corrugated fiberboard or the like at an excellent filling rate.
2. Description of the Prior Art
As well known, with improving civil life and consequent prospering business activities, various kinds of merchandise are traded in small and large quantities: hence, it is considered important to attain effective transport in distribution stages and effective display at shops as well as effective weighing and sorting processes in a distribution market.
Accordingly, in the weighing process, accurate, effective processing methods using high-tech such as so-called combined weighing technique have taken root; in the sorting process, a computer controlled high-precision processing technique is put in actual use utilizing bar code and pattern recognition means and other advanced means; and as for display at shops, various preferable forms from the viewpoint of sellers and purchasers are introduced utilizing special designs and interior techniques.
However, in transport such as collection and delivery at distribution stages including land transport, a cost-related important bottleneck to the distribution economy is hardly remedied, and forms of transport have been as they were.
Meanwhile, according to a popular form for trading merchandise in the distribution market, general consumer goods, particularly foods and the like are contained in sealed containers such as packing bags at a predetermined weight, such packing bags being of film sheets (including laminated sheets) of predetermined synthetic resins having no adverse effect on the quality of merchandise in many cases and being mass-produced stably at low costs for use at supermarkets and the like; usually, a so-called pillow type packing bag 1 as shown in FIG. 24 is used for business transactions, lateral heat seals 3, 3 being applied to a material film sheet 2 at both end portions thereof and also a longitudinal heat seal 4 being applied thereto for attaining a sealed state and thereby maintaining a sanitary condition and preventing deterioration in quality, an appropriate copy and instructions being printed on the bag; in some case, a quadrangular barrel type, i.e. so-called gusset type packing bag 1' in a steep rafter roof-like shape having a squeezed lateral heat seal 3' on a top plane and a longitudinal heat seal 4' is used, a bottom plane 5' being flat, the generally rectangular shape providing the merits of better stability and appearance when displayed at shops as compared with the aforesaid pillow type packing bag 1 and a relatively large containing capacity, thereby providing higher practical applicability.
Such forms are disclosed, for example, in Japanese Patten Application Laid-Open Publication Nos. 47-50155, 53-12880 and 58-15305.
Such packing bags (containers) used for selling include Tetra Pack and Pure Pack used widely for containing milk, juice and liquor and those having a spout on the top plane thereof for convenience in use.
Needless to say, various other three-dimensional packing bags (containers) including a box type are used in the distribution market.
However, the aforementioned conventional forms have the following problems which prevent the aforesaid transport cost related economic bottleneck from being remedied.
In other words, although the stable mass production associated with bag making/packing and cheap trading forms have taken root for the pillow type packing bag 1 in FIG. 24, packing in a predetermined case 8 of corrugated fiberboard or the like for transport of collection/delivery involves dead spaces 9, 9 . . . in the case 8 formed unavoidably due to relative arrangement of end portions of packing bags 1 stemming from the pillow type, and accordingly the filling rate reduces by the dead spaces 9, 9 . . . with a consequent reduction of at least 20% or more in some case in filling efficiency; needless to say, transport costs increase meaninglessly by the dead spaces 9, and hence the manufacturing side uses various devices for reducing the dead spaces 9 as much as possible in packing in the case 8, such as arranging bags like sashimi slices or overlapping top end portions when arranged in the lay-on-the-side posture; however, such devices are far away from a substantial solution because the problem derives from the form of packing; if it is forcibly attempted to increase the filling rate, the compaction will cause a demerit such as a damage to merchandise contained in the packing bags 1.
As for the gusset type packing bag 1' shown in FIG. 25, when packed in the upright posture or lay-on-the-side posture in the case 8, dead spaces 9', 9' . . . are also unavoidably formed due to a squeezed, sealed portion on the steep rafter roof-like formation as shown in FIG. 27, thus reducing the merit of relative surface-to-surface abutting arrangement of quadrangular packing bags 1', 1' . . . and accordingly putting a brake on a reduction in transport costs as in the case of the aforementioned form.
When packing the gusset type packing bags 1' in the case 8, there has arisen an obstacle to smooth packing due to the mutual interference and resultant deformation of lapped edge portions at squeezed, sealed portions.
Such a problem is also observed with Tetra Pack and Pure Pack.